1. Field of the Invention
The present invention relates to a data array conversion control system for converting data arrays between different kinds of processors such as Japanese word data processors or other word processors.
2. Description of the Prior
FIG. 1 is a block diagram showing an example of a data processing system employing a conventional data array conversion control system. As shown in FIG. 1, there are provided a first processor 37 and a second processor 38 in a first data processing unit 31 and there is also provided a third processor 39 in a second data processing unit 32 for processing data of a data array same as that of the data generated by the first processor 37 and for processing data of a data array different from that of the data generated by the second processor 38. The output data of the first and second processors 37 and 38 in the first data processing unit 31 are transferred to the third processor 39 in the second data processing unit 32 via a first data bus 35 and through a data array converting unit 33 and via a second data bus 36.
The mode of the operation of the data array converting unit 33 is selected between a normal mode and a twist mode. When the mode of the data array converting unit 33 is set to the normal mode, the data entered in the data array converting unit 33 are outputted without any conversion as shown in FIG. 2(a), and when set to the twist mode, the data entered in the data array converting unit 33 are outputted the data array is outputted after conversion as shown in FIG. 2(b). The selection between the normal mode and the twist mode is realized in response to receiving a mode switching signal generated by a mode switching unit 34 when the mode switching unit 34 receives a switch command signal sent from the first processor 37.
FIG. 3 shows another example of a conventional data processing unit employing a common memory unit 41, in addition, for delivery of data between the first data processing unit 31 and the second data processing unit 32. In FIG. 3, the first and second data processing units 31 and 32 are configured so that when character code data of a data array are transmitted from the first data processing unit 31 to the second data processing unit 32, the character code data of the same data array are processed in the second data processing unit 32, and that when image data of a data array are transmitted from the first data processing unit 31 to the second data processing unit 32, the image data of a different data array are processed in the second data processing unit 32. The character code data and the image data are respectively outputted from the first and second processors 37 and 38 in the first data processing unit 31 so as to be transferred to the third processor 39 in the second data processing unit 32 through the first data bus 35, data array converting unit 33, common memory unit 41, bus buffer 42 and the second data bus 36. It is also possible to gain access for writing data into storage of the common memory unit 41 from both of the first and second processing units 31 and 32 through an address selecting unit 40. The timing of the access to the common memory 41 is controlled by a control unit (not shown).
When the character code data and image data are respectively transferred from the first and second processors 37 and 38 to the third processor 39 at the same time, the data array converting operation is performed in accordance with a flow chart shown in FIG. 4.
That is to say, in the first step S1, the mode of the data array converting unit 33 is set to the normal mode in response to receiving the mode switching signal sent by the mode switching unit 34 on the basis of a switch command signal sent from the first processor 37. Subsequently in the step S2, the character code data of one word are generated from the first processor 37. The output character code data of the first processor 37 are transferred to the common memory unit 41 through the data array converting unit 33 without any array conversion. In the next step S3, the mode of the data array converting unit 33 is set to the twist mode in response to receiving the switch command signal sent from the first processor 37 to the mode switching unit 34. Next in the step S4, the image data of one word are generated from the second processor 38 and sent to the data array converting unit 33 where the data array of the image data is converted. The output image data with the converted data array are transferred from the data array converting unit 33 to the common memory unit 41. These operations are repeated hereafter until the process of the transfer data is completed.
As described above, since the character code data without any array conversion data array and the image data with their data array conversion are respectively stored in the common memory unit 41, the character code data and the image data read out from the common memory unit 41 can be processed without converting the data arrays in the third processor 39.
However, in the conventional data array conversion control system, the mode switching operation of the data array converting unit 33 is performed between the normal mode and the twist mode on the basis of the switch command signal sent from the first processor 37 to the mode switching unit 34, so that it is necessary that the switch command signals should be generated from the first processor 37 every time the transfer data generations are switched between the first and second processors 37 and 38 for generating the character code and image data respectively. In particular, when the image data are transferred from the second processor 38 to the common memory unit 41, since the switch command signal is generated from the first processor 37 at the same time of transferring the data from the second processor 38, the process of the data becomes complicated. Moreover, in the case that the accesses of the first and second processors 37 and 38 are performed in a time-shared data management, the data process becomes very complicated. Therefore, there is a problem that the data can not be transferred at a high speed.